Rhagomys rufescens, (Thomas 1886) (Thomas, 1886)

Steiner-Souza, Francisco, Cordeiro-Estrela, Pedro, Percequillo, Alexandre Reis, Testoni, André Filipe & Xix, Sérgio Luiz Althoff, 2008, New records of Rhagomys rufescens (Rodentia: Sigmodontinae) in the Atlantic forest of Brazil, Zootaxa 1824 (1), pp. 28-34 : 30-31

Other newly mentionned records of R. rufescens

Two individuals of Rhagomys rufescens were recorded at the Museu de Zoologia da Universidade de São Paulo, under the field numbers MZUSP 33889 and MZUSP 33890. Both specimens were obtained by Cristina Monteiro-Leonel at the locality of Retiro-Branco (21°47’S, 46°31’W), Poços de Caldas , Minas Gerais state, in a property of ALCOA Alumínio S.A. The site has a total area of 6,44 ha and is located at 1.553 m of altitude in the high plateau of Poços de Caldas , Minas Gerais. The area has suffered great anthropogenic impact being deforested and the superficial layer of soil removed for bauxite mining between 1978 and 1981. Around 1983, the area was recovered and reforested ( Monteiro-Leonel 2004). In the neighboring areas, the vegetation consists of a mosaic, with transition areas between semi-deciduous forest, evergreen mixed forests and cerrado (savanna-like vegetation; Nappo et al. 2005). At the capture site, leaf litter is abundant, the canopy is not continuous, but presents a dense arboreal stratum formed by young trees and bamboo. The trees have a mean diameter at breast height of 15cm and 20m of mean height ( Nappo et al. 2005).

The three new individuals from the state of São Paulo were collected by A. A. Bueno and R. Pardini (pers. comm. and unpubl. data). One of the individuals was captured near the city of Ibiúna in a fragment of closed forest in the Reserva Florestal do Morro Grande, where two other specimens of R. rufescens have been registered ( Pardini & Umetsu 2006). Method of capture, elevations and detailed description of the relief can be obtained in Metzger et al. (2006) and Pardini and Umetsu (2006). The other records are two individuals collected with pitfalls traps of 60 litres in a continuous forest adjacent to the Parque Estadual de Intervales, in Ribeirão Grande. With a vegetal physiognomy similar to the one found in the Reserva Florestal do Morro Grande, the areas are composed of mature or secondary forests that have an intense and selective deforestation with altitudes ranging from 800-1000m.

The northernmost occurrence of R. rufescens was discovered by M. Passamani (pers. comm. and unpubl. data). The study area (19º 58`S e 40º 35`W) is close to Estação Ecológica de Santa Lúcia, in Santa Teresa. The area is covered by Atlantic Forest in good stage of conservation, in altitudes ranging from 795-873 m. The capture was made with Sherman traps. The baits used were composed of banana and a mixture of cornmeal, peanut and oil of liver cod (Scot emulsion).

General geographic distribution

The new occurrences documented in the present work in addition to existing data on R. rufescens identified the southernmost occurrence of the species within the Atlantic forest around Indaial , Santa Catarina (27°02’S, 49°08’W), and the northernmost in the surroundings of Santa Teresa , Espírito Santo State (19º58`S e 40º35`W), localities which are separated by at least 1173 km. All the known specimens / records of R. rufescens are summarized in Table 1 , consisting in one individual from Viçosa ( Mata do Paraíso ), Minas Gerais state; one individual from Ubatuba ( Parque Estadual da Serra do Mar ), two from Morro Grande ( Reserva Florestal do Morro Grande ), both in São Paulo state; the holotype described by O. Thomas supposedly from Rio de Janeiro state and two additional specimens without precise information ( Pinheiro et al. 2004; Percequillo et al. 2004; Pardini & Umetsu et al. 2006).

GIS plotting of collecting localities indicate that R. rufescens occurs mainly in or nearby montane forests ( Fig. 1 ).

Figures

FIGURE 1. Collecting localities of Rhagomys rufescens. The details of localities are specified in Table 1. In light green lowland forests, in dark green montane forests with altitude range of 500–1000m, and in brown montane forests with altitudes superior to 1000 m. Vegetation map at 1 km resolution from Eva et al. (2002).